Broom heads of the push type are commonly known. Further, such broom heads are used on many diverse floors and other surfaces for both residential and commercial applications.
Typically, the design of a push broom head is approached with one or more specific applications in mind. Single purpose broom designs have not been preferred, but are often the accepted approach because of the limited success of more versatile broom designs. Design considerations generally take into account the type of debris that is anticipated in use—such as fine or coarse particles of dirt or debris—and the roughness or smoothness of the surface to be swept. In an effort to avoid the need to use more than one broom, each with different types of bristles to remove different types of debris, some conventional broom heads combine bristles of different stiffness into a single broom head.
One intention of a dual-bristle design is to provide an implement that can sweep both fine and coarse particles of debris in one operation. The thought is that as the broom is pushed, a forward row of coarse bristles will loosen and move the heavy particles of dirt while a rear row of less coarse bristles will loosen and move the finer materials that are not picked up by the coarser bristles. Some conventional dual-bristle broom heads consist of a finer-bristled, softer border with a coarser, stiffer center section. However, in many applications, this wastes the effectiveness of a significant number of the bristles, particularly the leading edge of softer/finer bristles.
U.S. Pat. No. 2,043,758 ('758 Lay) discloses a street push broom having a single forward row of coarse bristles and a single rear row of longer, finer bristles. In normal use, the broom head is supported at an angle as the brush head is pushed over a surface. However, while such designs may work on a wider range of particles, they do not necessary operate effectively on a wide range of surfaces, which can range from smooth to quite rough. It also has been found that such angled sweeping action can produce excessive and premature wear on the forward bristles, thereby reducing both the service life and effectiveness of the broom. Moreover, without a varying degree of “preload” (which is generally accomplished by the angle of the trim in conjunction with the angle of the handle of the broom dictated by the angle of the hole in the block), a broom head may not be effective for reaching into many surface irregularities.
Further, conventional dual-bristle-type broom heads (such as the type disclosed in the '758 Lay Patent) often have a limited range of applications that may not provide the desired range or degree of versatility. Commonly, such broom heads are limited to single or narrow bands of forward rows of coarser, non-angled bristles. In some instances, such as when a great deal of debris of various sizes is being swept, the single or narrow bands of coarser rows may fail to catch or move the type of debris that it is intended to collect.
Moreover, conventional push broom heads typically employ level, non-angled bristle fiber trims of at least 2.875 inches, with 3.0 to 3.25 inches being most common. Brooms meant for rougher and/or larger debris generally have longer trim. Garage brooms employ a “standard” trim of 4.0 inches and street brooms, such as that disclosed in the '758 Lay Patent, have the longest trim length—in excess of 4.0 inches, and most typically 5.25 to 6.25 inches. Such conventional broom heads commonly do not employ reduced-diameter bristle fibers. Failure to incorporate reduced-diameter fibers into a broom head design can ignore or overlook several important advantages. Among other things, smaller diameter fibers can typically reach into finer surface irregularities. Further, provided that the relative stiffness of the fibers being compared are similar, more small-diameter fibers can be fit into a given construction area on a broom head, thereby providing a greater number of cleaning tips, which can reinforce one another, and potentially greater cleaning effectiveness for a comparable area of broom head.
As such, there exists a need in the industry for an improved broom head design that, among other things, (i) is suitable for use over a wider range of surfaces and applications; (ii) improves the effectiveness of the sweeping action and incorporates tufts of different types of bristles having reduced diameter fibers and/or different angles of attack; (iii) improves the length of service and effectiveness of the various bristles and helps to prevent premature wear; (iv) reduces the amount of bristle material required; and/or (v) is relatively simple to construct using conventional materials and equipment.